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Abstract. During the last glacial period Northern Hemisphere climate was characterizedby extreme and abrupt climate changes, so-called Dansgaard–Oeschger (DO)events. Most clearly observed as temperature changes in Greenland ice-corerecords, their climatic imprint was geographically widespread. However, thetemporal relation between DO events in Greenland and other regions isuncertain due to the chronological uncertainties of each archive, limitingour ability to test hypotheses of synchronous change. In contrast, theassumption of direct synchrony of climate changes forms the basis of manytimescales. Here, we use cosmogenic radionuclides (¹⁰Be,³⁶Cl, ¹⁴C) to link Greenland ice-core records toU∕Th-dated speleothems, quantify offsets between the two timescales, andimprove their absolute dating back to 45000 years ago. This approach allowsus to test the assumption that DO events occurred synchronously betweenGreenland ice-core and tropical speleothem records with unprecedentedprecision. We find that the onset of DO events occurs within synchronizationuncertainties in all investigated records. Importantly, we demonstrate thatlocal discrepancies remain in the temporal development of rapid climatechange for specific events and speleothems. These may either be related tothe location of proxy records relative to the shifting atmospheric fronts orto underestimated U∕Th dating uncertainties. Our study thus highlightsthe potential for misleading interpretations of the Earth system whenapplying the common practice of climate wiggle matching.